Used in computing and telecommunications for the person or system that sends a message, email, or data.
Please check the sender of the email.
A suspicious email arrived, so I checked the sender.
The scam email disguised its sender as a well-known company.
送信者 is used for electronic messages like email, while 差出人 is the traditional term for the sender's name on a letter or parcel.
送信者 is the one who sends a message, while 受信者 is the one who receives it.
Compound of 送信 (transmission) and 者 (person).